There are many doctors in China, but the average score is only one tenth of that in the United States. If the gold content of doctoral degrees in the United States is 100%, followed by Britain, with gold content of about 84%, Japanese 58% and German 44%, then the average gold content of doctors in China may be only 10%. Of course, this is the average score, depending on the individual's performance.

Doctoral degree is generally a research degree, and the qualification for obtaining this degree depends mainly on the research results besides passing the basic qualification examination. The measurement of research results mainly depends on the number of papers published in internationally renowned academic journals and the number of times the papers are cited. Therefore, the average level of doctoral degrees in different countries can be quantitatively measured by the average number of papers published by doctoral degree winners in well-known journals and the average number of papers cited.